Sunday, 8 November 2009

In the Glow

Filed under: Uncategorized — Michael @ 18:04

I really don’t understand the folks in the audiophile community that claim that tube amplifiers sound better than transistor units. I mean, for some time now, solid-state audio amplifiers have been capable of reproducing the input signal with virtually perfect fidelity.
Maybe I should say ‘didn’t understand’. Let me explain.
In my home system I use a NAD C315BEE and am absolutely pleased with it. When, a few months ago, I went looking for a system, I listened to a number of amps and honestly couldn’t really hear any difference between most of them. I choose the NAD because it was relatively inexpensive and had all of the features I needed. Before then I listened with headphones using a couple of amplifiers I built myself, one with op-amps and another, class-A amp, using discrete transistors. Both sound very good with the class-A amp being, marginally, my favorite.
Anyway, I got to thinking it would be interesting to hear a tube amp and see, er, hear, if there really was something to it. I found a simple headphone amp circuit (http://headwize.com/projects/showfile.php?file=waarde1_prj.htm) that many have built and given positive comments about. Here is a pic of my result.

TubeHeadphoneAmp
(The whole box is 20cm (8″) wide, 30cm (12″) deep and 12cm (4.5″) high. The big tube is just under 13cm (5″) tall. The actual amp is completely built on the lower plate. That’s why the input, volume control and output jack are “on top”. The rest is the power supply. The two switches control the filament and high-voltage separately to let it warm up before applying the real juice.)

Well, I have now listened to the warm (er, hot) glow of tubes and can report that the sound is really quite pleasing. It definately has a different character than with my other semiconductor amps. So, what makes it so? I have some thoughts on that. First, no question that the fidelity of the playback is comprimised. But the odd thing is, in a somehow “good” way. The sound of a violin or soprano, e.g., is softer. And bass sounds such tympani or bassviolin roll in rather than pound in. It really does give an impression of a “rounder” sound. (But I don’t want to imply that the sound from the tubes is more accurate. It’s not. Violins can be hard and tympani really do pound.)
I have an analogy. With my class-A amp, for example, everything in the recording is reproduced with, for all intent, no loss in fidelity. I close my eyes and I am alone in the second row of the auditorium, right behind the conductor (or depending on the mastering, in the orchestra) and I can hear everything in analytic detail. With the tube amp I am in the first balcony with friends around me. I mean there is no longer the analytical precision but the sound of life is around. Or something. It is “verblüffend” (a good German word meaning baffling/intriguing/fascinating all at once).
Now, I have heard only one circuit, one tube type, etc. But I think that this “good” fidelity loss would be somewhat different with other choices. Can this be what the tube-heads are really chasing? I mean the good loss that best satisfies them?
So, will I use it regularly? Probably. It was fun to build and does, in fact, sound really nice. But it comes with some minuses. It’s heavy. No, not that way, I mean really heavy as in weighs a lot. The high-voltage supply has to deliver almost 10 watts at 150V with no ripple. That means lots of transformer, lots of capacitance and a big inductor. And the 6V supply for the heaters is cruising at over 15W. Another big transformer and more capacitors and a voltage regulator that needs a huge heatsink (and it still gets too hot to touch after a couple hours).
But it’s pretty, glowing there in a darkened room. Maybe that is the real draw.

Sunday, 6 September 2009

Hi!

Filed under: Uncategorized — Michael @ 15:38

Well, it has certainly been some time time since the last post. The blog was, in fact, not even available for a while because of a hack attack. It took some time to get it back up and running but here I am again. I really don’t know what is in it for the attackers. In my case it was a bunch of additional invisible admin accounts and lots of crap spam comments. Ho hum.
Anyway, over the next few weeks I will be posting a couple of things about an interest of mine that I have not touched on here and that is amateur astronomy.
And if you haven’t already, check out my Magic Flute site at themagicflute.info. It’s a rambling collection of posts about my favorite opera, Mozart’s “Die Zauberflöte”. There’ll be more to come there as well.

Tuesday, 4 March 2008

Microsoft, again

Filed under: Uncategorized — Michael @ 1:15

I just saw a news report about Microsoft at CeBIT and the big thing was their “new” Surface interface. (Well, actually the report began with the decision of the EU to impose an 899 million Euro fine on MS for failing to live up to the decision in 2004 that MS must make their software APIs available to others. Google “eu microsoft”. Check out, e.g., the NY Times article.)
Anyway, here again is MS telling us that they have developed the coolest and the greatest when in fact they must have seen this (from 2006 at TED): Jeff Han: Unveiling the genius of multi-touch interface design.
Now admittedly, this is what TED is all about, i.e., sharing ideas. And maybe MS licensed this technology, all above board. Great if they incorporate this into their OS. Apple has done something similar in their iPhone/iPod Touch devices. But Microsoft again implies that technology such as “Surface” does not exist outside of their world. And that is just not the case. It seems there are very few (if any) really innovative ideas coming out of Redmond. But they sure know how to claim other’s as their own.

Friday, 29 February 2008

Another example of why Microsoft pisses me off

Filed under: Uncategorized — Michael @ 0:53

I just saw a TED talk about the “new” Microsoft World Wide Telescope project (http://worldwidetelescope.org/) and it pissed me off. Not because the project is a not a worthy one. In fact it looks like a very cool thing. But it was the usual, from them, implication that this was something “new, never been done before and only Microsoft brings you this kind of thing” that pissed me off when in fact a similar application has been around since 2001. The application is Celestia (http://www.shatters.net/celestia/). If the WWTelescope sounds interesting, you should check out Celestia, too. It also provides tours of the universe and supports scripting and add-ons and has a huge community of contributors and (this is probably where the folks in Redmond want you to stay ignorant) runs on just about every platform out there (including Windows). Oh, and is also free.
It pisses me off because it is just another example of how “computing” is what Microsoft defines it to be and not what it really is. There are alternatives. Computing (without the quotes) is a wide open playground. “Computing” is what Microsoft says it is and what you must agree to if you want to play.

Friday, 30 March 2007

Tinker Bell and electrons

Filed under: Uncategorized — Michael @ 22:47

A recent round of correspondence reminded me of an old theory of mine. So, this post is part autobiography, part philosophy and part speculative fiction. Here goes…
I grew up in San Jose, California. This was in the sixties, before this once small town became part of what is now known as Silicon Valley. The area south of San Francisco acquired that appellation because the first tech-industry there was the fabrication of semiconductors (made from silicon) and not so much the computer and software companies that so dominate the landscape now. Anyway, when I graduated from high-school (in 1971) I didn’t know what I wanted to do and started studying math at the local college. I had an interest in electronics and had even built a couple of pieces of amateur radio gear and some audio stuff. So, to help pay the bills, I started, in 1974, to work for a chip company as a technician. These were pretty rough and tumble times with rapid growth and it was definitely an employees market. I was clever enough to pick up enough knowledge on the job so that within a couple of years I was doing some pretty cool engineering and getting paid for it. Bye to school and into the tech-world.
I mention all this in order to indicate that I am pretty well grounded in semiconductor physics, logic and design. Of course, the circuits I worked with then were fabricated with geometries considerably larger than today but the concepts have changed little. (In fact, I sometimes think that the progress should have been even faster than it has been since what exists today is, for the most part, just a refinement of what I was playing with then. Ho hum.)
But at some point I realized that what we were building was impossible. I mean, a semiconductor device is built on a size-scale that is really mind-bogglingly small. Today, the state change of a transistor in a typical IC is the result of the movement of only a few dozen electrons. And electrons are really, really small. Possibly not even “real”. Maybe it was the experience of watching and single-step clocking ICs under power in a scanning electron microscope (while stoned, and quite an experience it was, too) that first lead me to this theory of mine.
I call it the “Tinker Bell Theory”.
You surely remember watching Mary Martin as Peter Pan when you were small. For those who have a serious gap in their cultural training, Peter Pan is a play where a young boy refuses to grow up (I can identify) and he has a “sidekick” fairy named Tinker Bell. At a point in the play where Tinker Bell drinks some poison (that was meant for Peter) and is dying, Peter turns to the audience for help and pleads that they believe in fairies to save “Tink”. He says to clap your hands if you believe and of course no one can kill a fairy and so everyone claps and all is well once again.
The point is to believe. It occurred to me that semiconductors work because from Shockley on, engineers believe that they do. And when things go wrong and your PC eats that file you’ve been working on for the last few hours and there’s no backup it is because, just for a moment perhaps, a semiconductor engineer somewhere (probably Intel) doubted.
Of course disk drives are impossible, too. Apply my theory and it easy to see that if someone at Fujitsu, Seagate, Toshiba, Western Digital or where ever thinks “damn, that’s impossible!” then poof, heads contact platter and adios baby.
Well, that’s my theory. I think it is at least as good as Intelligent Design.
“I’ll never grow up, never grow up…”

Sunday, 18 February 2007

Our little bumblebee

Filed under: Uncategorized — Michael @ 23:21

Just a quick post with a picture of “Hummel” (German for bumblebee), our new family member.

She’s been with us a week now. Both blackcat and I are very glad to have this new little “Wesen” (being, creature) sharing our home. We have the feeling that Hummel is happy with us too. It is obvious that she was mistreated in the past but she is quickly learning to trust us and that is good feeling.

Monday, 12 February 2007

The world turns…

Filed under: Uncategorized — Michael @ 0:30

Today, Sunday, we adopted a cat. Yesterday, my wife, blackcat, opened the bi-weekly newspaper for our neck-of-the-woods and turned immediately to the section that more often than not contains an article from the local “Tierheim” (animal shelter). There was a picture of “Hummel” (bumblebee). The description of this cat seemed to match what we had discussed as our desire for a new member of the family exactly. She was an adult cat (~six years old) and had had a less than pleasent life and needed a new home that was quiet and where she would be the only cat.
blackcat called the Tierheim the next morning and well, a short while later Hummel was being introduced to her new home. She seems to adapting well to her new surroundings. It will take a few days before she really feels at home. And she is at home. We made the decision to bring her into our life and she is now our responsibility. We can not, like those before, simply throw her away.
Follow-up and a picture will follow.

Sunday, 4 February 2007

The State of Audio

Filed under: Music,Uncategorized — Michael @ 23:26

Music has been an important part of my life for as long as I can remember. I don’t play a musical instrument but I do listen to music of all kinds both live and recorded. (Well, that’s not strictly true. I don’t listen to all kinds, just good music.) Since I listen to recordings I have also had a parallel interest in sound reproduction. You know, hi-fi and all that. I have a technical background and am fortunate enough to have the skills needed to have built some of the electronics I currently use.
But of course I can’t build a CD-player or pair of headphones (well, I suppose I could if I had the necessary equipment but then that would cost way more than the items would) so that means occasional product research and purchase at the HiFi store and/or on the Web. Some of what I see there just amazes me. I don’t mean in the sense of the current state of the art in sound reproduction. That has steadily improved to a point where a modest expenditure can give you a system that will produce fantastic fidelity. No, what amazes me is the complete disregard for physics, and logic, that permeates the “high-end” audio market place. Vinyl records played on 10.000 dollar turntables. Tube amplifiers. (“Vastly superior” sound than from a CD or transistor, respectively.) Shielded power cords. Specially braided speaker cables. CD demagnitizers. And all for LOTS of money.
I recently ran across a Web-site, http://www.bruce.coppola.name/audio/wisdom.html, by Bruce Coppola that does a good job of bringing together information for the rational among us that just want the best fidelity for our money (and a laugh at the expense of the “golden ears”). Check it out.

Friday, 8 December 2006

We lost a friend today

Filed under: Uncategorized — Michael @ 22:47

Sixteen years ago a young cat showed up at our door. He had been abandoned. We lived in a rural area and he was not the first cat that someone had thrown away in the area. But this cat was not feral and was probably tossed when, as male cats do, he started spraying. We took a liking to him and after a few days we decided we would adopt him. That meant a visit to the Vet for shots and neutering. I named him Jupiter. He was a very gentle cat and we quickly became very attached him and he to us. Our other cat, Tasha, even gradually came to tolerate him.
Five years later, I got a job offer that meant moving from central California to Germany. My wife’s only concern about the move was whether we would be able to bring along our cats. We could and we did.
Sadly, Tasha died a couple of years later. That was in 1997. She was almost seventeen years old. Her death left a large empty spot in our “family”.
Today, it was Jupiter who left us. He was a good friend. We will miss him. Very, very much.

Jupiter

Saturday, 2 December 2006

Our London Visit – Turkey Day 2006

Filed under: Uncategorized — Michael @ 22:39

Well, blackcat and I were in London (Reading, actually) this past week and we had a great time. The main reason for the trip was to visit with our good friends P. and K. and cook up a Thanksgiving feast. Preparations began on Friday with shopping and making the desserts. The party was on Saturday. As usual, I did the turkey and stuffing. This year P. did a great dressing and I think that he should prepare the bird next year. (And I can spend more time on pies!)
This was our eighth year together. It has become quite a tradition. Many of the guests from previous years have also become regulars. Even though blackcat and I only see them once a year, it always seems like it was only last weekend. It’s that kind of group.
This year P.’s sister flew in from Athens to be there for her first Thanksgiving. It was great to meet her. Unfortunately, K.’s brother couldn’t make it this year. There’s always next year.
It was a fine day. I’m already looking forward to next year.